Without a sweat, I recently changed from Ubuntu to NixOS on a server I have access to only via SSH (so mounting an ISO wasn't an option) using[0], so the switch

Without a sweat, I recently changed from Ubuntu to NixOS on a server I have access to only via SSH (so mounting an ISO wasn't an option) using[0], so the switch happens live(!) and when you reboot you end up in NixOS. I've also done it to CentOS 7.5, but manually via[1]. It was the case here that backups were not necessary, but it's pretty incredible what's possible when the system configuration is declarative and only /nix and /boot are needed by NixOS to boot. I highly recommend people new to running servers to try NixOS. [0] https://github.com/elitak/nixos-infect https://github.com/elitak/nixos-infect [1] https://nixos.org/manual/nixos/unstable/index.html#sec-installing-from-other-distro https://nixos.org/manual/nixos/unstable/index.html#sec-insta...